Next generation sequencing of small RNAs isolated from exosomes in human semen

Preparation of exosomes isolated from semen contain a substantial amount of RNA, mostly from 20 to 100 nucleotides in length. We sequenced separately 20-40 and 40-100 nucleotide fractions of RNA from exosomes isolated from semenal fluid from six healthy donors. We found various classes of small non-coding RNA, including mature microRNA and piwi-RNA, as well as abundant Y RNAs and tRNAs present in both full length and fragmented forms. Specific RNAs were consistently present in all donors. For example, fifteen (of ~2,600 known) microRNAs constituted over 80% of mature microRNA in SE. Additionally, tRNA fragments were strongly enriched for 5’-ends of 18-19 or 30-34 nucleotides in length. Size-fractionated small RNA profiles from exosomes isolated from the seminal fluid of six healthy donors